A driven mechanism for a wafer cleaning device and a wafer cleaning device

Abstract

The application discloses a driven mechanism for a wafer cleaning device and the wafer cleaning device, which comprises a base, an installation cavity formed in the inside of the base, a rotating shaft connected to the installation cavity through a rotating transmission assembly, a first end of the rotating shaft extending from the base, a wafer supporting unit concentrically and coaxially connected to the rotating shaft for supporting the wafer, a structural member sealingly connected to the base, part of the structural member extending into the installation cavity and abutting against the rotating transmission assembly, and a sensor assembly connected to the rotating shaft for monitoring the number of rotations of the rotating shaft relative to the base. The wafer rotates to drive the wafer supporting unit to rotate, the rotating shaft synchronously rotates to drive the sensor assembly to rotate, and the number of rotations of the wafer is monitored. The wafer rotates to drive the wafer supporting unit to rotate, the rotating shaft synchronously rotates and cooperates with the sensor assembly to realize the monitoring of the rotation speed of the wafer, the mass and the torque of the rotating shaft are small, the moment of inertia of the rotating shaft and the wafer supporting unit is reduced, the monitoring of the rotation speed of the wafer is more accurate, and the cleaning effect is better.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of semiconductor integrated circuit chip manufacturing, and particularly relates to a driven mechanism for a wafer cleaning device and the wafer cleaning device. BACKGROUND

[0002] Chemical mechanical polishing is a kind of global planarization ultra-precision surface processing technology. Since a large amount of chemical reagents and abrasives used in chemical mechanical polishing will leave a large amount of polishing particles and polishing byproducts and other pollutants on the wafer surface after polishing, the pollutants on the wafer surface need to be removed to avoid the pollutants re-staying on the wafer surface before the process. Therefore, the wafer surface needs to be cleaned for multiple times in the wafer manufacturing process to remove the pollutants such as metal ions, atoms, organic matters and particles attached to the wafer surface. The cleaning includes three process units: a megasonic cleaning unit, a brushing unit and a drying unit. The brushing unit mechanically acts on the wafer surface through a roller brush to make the pollutants on the wafer surface separate into the cleaning liquid, and on the other hand, utilizes the chemical reaction between the cleaning liquid and the pollutants on the wafer surface to make the pollutants dissolve in the cleaning liquid.

[0003] The existing wafer cleaning device usually places the wafer in the brushing device, drives the wafer to rotate through the driving wheel, and at the same time, the roller brush brushes the wafer synchronously, and at the same time, the driven wheel rotates with the wafer to detect the rotation speed of the wafer. In the process of executing the above operation, the rotation speed detected by the driven wheel may drop, and the rotation speed of the wafer will directly affect the cleaning effect. In addition, the structure bearing is in a dry grinding state without other lubricants, and the whole structure has large resistance. Moreover, the current rotating structure has large mass and large inertia, and has large starting resistance. SUMMARY

[0004] In order to overcome the deficiencies of the prior art, the present application provides a driven mechanism for a wafer cleaning device and the wafer cleaning device, which utilizes the rotation of the rotating shaft to realize the monitoring of the rotation number of the wafer, greatly reduces the rotational inertia, and makes the monitoring of the rotation speed of the wafer more accurate.

[0005] The technical scheme adopted by the present application to solve the technical problems is as follows: a driven mechanism for a wafer cleaning device, comprising:

[0006] a base for fixedly connecting to the wafer cleaning device, the base being hollow inside to form an installation cavity;

[0007] a rotating shaft rotatably connected to the installation cavity through a rotary transmission assembly, the first end of the rotating shaft extending out of the base;

[0008] a wafer supporting unit concentrically and coaxially connected to the first end of the rotating shaft for supporting the wafer;

[0009] a structure member, which is sealingly connected to the base and at least partially extends into the mounting cavity and is abuttable to the rotation transmission assembly;

[0010] a sensor assembly, which is at least partially connected to the rotation shaft and is used to monitor the number of rotations of the rotation shaft relative to the base;

[0011] When the wafer rotation drives the wafer supporting unit to rotate, the rotation shaft synchronously rotates and drives at least part of the sensor assembly to rotate, so as to monitor the number of rotations of the wafer.

[0012] Further, the wafer supporting unit comprises a sleeve part connected to the rotation shaft, a connecting part extending radially outward from the end of the sleeve part, a fixing part matched with the connecting part, and a clamping groove part clamped between the connecting part and the fixing part, the clamping groove part being used to contact the wafer, and the sleeve part being wrapped around the periphery of the base along the radial direction and the axial direction.

[0013] Further, the rotation transmission assembly comprises a first bearing, a second bearing, and a limiting part abutting between the first bearing and the second bearing.

[0014] Further, the clamping groove part is radially matched with the limiting part.

[0015] Further, the sensor assembly comprises a metal body and a sensor matched with the metal body, the metal body being connected to the second end of the rotation shaft, and the sensor being arranged on the structure member.

[0016] Further, a liquid passage is arranged, which at least comprises a liquid inlet channel arranged on the structure member, at least two branch channels diverged from the liquid inlet channel, a liquid storage channel arranged on the portion of the mounting cavity corresponding to the rotation transmission assembly, and a bypass channel, the bottom of the liquid storage channel being arranged at a height lower than the inlet of the bypass channel.

[0017] Further, the liquid flow in the liquid inlet channel is 30-70ml / min, and the liquid flow in the branch channel is 7.5-17.5ml / min.

[0018] Further, the terminal end of the liquid passage is provided with a dynamic sealing ring, and the starting end of the liquid passage is provided with a one-way valve, so that the liquid passage is closed and the liquid storage channel is filled with liquid.

[0019] Further, the moment of inertia of the rotation shaft and the wafer supporting unit is less than 35kg*mm 2 .

[0020] The application further discloses a wafer cleaning device, which comprises a cleaning box body, a driving wheel mechanism arranged in the cleaning box body and used to drive the wafer to rotate, a brushing mechanism used to clean the surface of the wafer, and the above-mentioned driven mechanism.

[0021] The beneficial effects of the present application are: 1) the wafer rotation drives the wafer support unit to rotate, so that the rotating shaft rotates synchronously and cooperates with the sensor assembly to realize monitoring of the wafer rotation speed, the base and the structural member do not rotate, the mass and the moment of the rotating shaft are smaller, the moment of inertia of the rotating shaft and the wafer support unit is greatly reduced, the monitoring of the wafer rotation speed is more accurate, and then better cleaning effect can be achieved by using wafer transfer adjustment; 2) the liquid passage is designed to water lubricate the rotating transmission assembly, reduce the friction coefficient of the bearing, help the bearing to better dissipate heat, and prolong the service life of the rotating transmission assembly; 3) the liquid passage is inhibited three times, reducing the influence of water lubrication on the rotating shaft rotation, ensuring the accuracy of the wafer rotation speed monitoring; 4) the rigid body moment of inertia of the rotating shaft and the wafer support unit is small, only lower static friction is needed to make it rotate, reducing the wear amount of related consumables, improving stability while reducing consumable cost and improving machine output per unit time; 5) the clamping groove piece is arranged in radial correspondence with the limiting piece, the center of gravity of the driven mechanism is close to the directly below of the wafer, the first bearing and the second bearing are relatively balanced in stress, the problem of excessive wear of one side bearing caused by unbalanced load is reduced, and the machine output per unit time is improved. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 It is a partial perspective view of the wafer cleaning device related to the present application.

[0023] Figure 2 It is a sectional view of the driven mechanism related to the present application Figure 1 .

[0024] Figure 3 It is a sectional view of the driven mechanism related to the present application Figure 2 .

[0025] Figure 4 It is a perspective view of the driven mechanism related to the present application Figure 1 .

[0026] Figure 5 It is a perspective view of the structural member related to the present application Figure 1 .

[0027] Figure 6 It is a perspective view of the structural member related to the present application Figure 2 .

[0028] Figure 7 It is a perspective view of the fixing member related to the present application.

[0029] Figure 8 It is a sectional view of the fixing member and the metal body related to the present application.

[0030] Figure 9 It is a side view of the driven mechanism related to the present application.

[0031] Figure 10 A perspective view of a base and wafer support unit according to the present application Figure 2 .

[0032] Figure 11 A perspective view of a base and wafer support unit according to the present application

[0033] Figure 12 A perspective view of a base and wafer support unit according to the present application

[0034] Figure 13 A sectional view of a driven mechanism according to the present application Figure 3 .

[0035] Figure 14 A sectional view of a driven mechanism according to the present application Figure 4 .

[0036] wherein, 1 - a wafer cleaning device, 11 - a cleaning box body, 12 - a driving wheel mechanism, 13 - a brush cleaning mechanism, 2 - a base, 21 - a mounting cavity, 3 - a rotating shaft, 31 - a first end of the rotating shaft, 32 - a second end of the rotating shaft, 4 - a rotary transmission assembly, 41 - a first bearing, 42 - a second bearing, 43 - a limiting piece, 5 - a wafer support unit, 51 - a sleeve part, 52 - a connecting part, 53 - a fixed part, 54 - a clamping groove piece, 541 - a notch, 55 - an inclined guide surface, 6 - a structure piece, 61 - an external guide pipe, 7 - a sensor assembly, 71 - a metal body, 72 - a sensor, 721 - a sensor press fitting piece, 73 - a fixing piece, 8 - a liquid passage, 81 - an inlet passage, 82 - a branch passage, 83 - a liquid storage passage, 84 - a detour passage, 85 - a dynamic sealing ring, 9 - a wafer. DETAILED DESCRIPTION

[0037] In order to make the person skilled in the art better understand the present application, the technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by the person skilled in the art without creative labor should belong to the protection scope of the present application.

[0038] As shown in Figures 2-4 a driven mechanism for a wafer cleaning device, comprising a base 2, a rotating shaft 3, a wafer support unit 5, a structure piece 6 in sealing connection with the base 2, and a sensor assembly 7.

[0039] As shown in Figure 11 , Figure 12As shown, the base 2 is used to fix the driven mechanism to the wafer cleaning device 1. The interior of the base 2 is hollow to form a mounting cavity 21. One end of the mounting cavity 21 is completely open. A part of the structural component 6 extends into the mounting cavity 21 from this end and is sealed to the base 2. Specifically, the outer ring of the structural component 6 can be detachably assembled to the outer ring of the end of the base 2. The other end of the mounting cavity 21 is partially open.

[0040] The rotating shaft 3 is rotatably connected to the mounting cavity 21 via the rotary transmission assembly 4, and the first end 31 of the rotating shaft 3 extends out of the base 2 from a partially open position in the mounting cavity 21. In this embodiment, the rotary transmission assembly 4 includes a first bearing 41 and a second bearing 42 sleeved on the outside of the rotating shaft 3, and a limiting member 43 abutting between the first bearing 41 and the second bearing 42. The first bearing 41 abuts against the inner end face of the base 2. The structural member 6 extends into the mounting cavity 21 and abuts against the second bearing 42 of the rotary transmission assembly 4, thereby securely assembling the first bearing 41, the limiting member 43, and the second bearing 42 within the mounting cavity 21, ensuring the stable installation of the rotary transmission assembly 4, preventing axial movement of the first bearing 41 and the second bearing 42 on the rotating shaft 3, and ensuring their positional stability.

[0041] The wafer support unit 5 is concentrically and coaxially connected to the first end 31 of the rotating shaft 3, and its function is to support the wafer 9. In this embodiment, the wafer support unit 5 includes a sleeve portion 51 connected to the first end 31 of the rotating shaft 3, a connecting portion 52 extending radially outward from the end of the sleeve portion 51 toward the structural member 6, a fixing portion 53 cooperating with the connecting portion 52, and a slot member 54 clamped between the connecting portion 52 and the fixing portion 53. The slot member 54 is used to contact the wafer 9, and the sleeve portion 51 covers the periphery of the base 2 radially and axially.

[0042] like Figures 10-12 As shown, the fixing part 53 is a hollow annular structure, which is sleeved on the sleeve part 51 and fixedly assembled with the connecting part 52, thereby clamping the slot member 54 between the two. In order to facilitate the insertion of the wafer 9 into the slot member 54 and to provide better support for the wafer 9, the opposing sides of the fixing part 53 and the connecting part 52 are formed with inclined guide surfaces 55, and the end of the inclined guide surface 55 is connected with the slot opening 541 of the slot member 54.

[0043] There is a certain friction between the clamping groove part 54 and the wafer 9. When the wafer 9 rotates at a certain speed, the clamping groove part 54 will also rotate synchronously at the same speed, so that the corresponding connecting part 52 will also rotate synchronously at the same speed, and then drive the rotating shaft 3 to rotate synchronously. At this time, the rotating transmission assembly 4 forms a good support and transmission effect on the rotating shaft 3, reduces the vibration and deviation of the rotating shaft 3, and ensures the stable operation of the rotating shaft 3. The clamping groove part 54 is a consumable for fixing the wafer 9, which needs to be replaced regularly. The detachable assembly of the fixing part 53 and the connecting part 52 can facilitate the replacement of the clamping groove part 54.

[0044] The relative position of the connecting part 52 and the base 2 is such that the clamping groove part 54 corresponds to the limiting part 43 in the radial direction, and preferably the notch 541 of the clamping groove part 54 corresponds to the middle part of the limiting part 43.

[0045] As shown in Figure 3 , Figure 7 , Figure 8 The sensor assembly 7 is connected to the rotating shaft 3 for monitoring the number of revolutions of the rotating shaft 3 relative to the base 2. In this embodiment, the sensor assembly 7 includes a metal body 71 and a sensor 72 cooperating with the metal body 71. The metal body 71 is connected to the second end 32 of the rotating shaft 3, and the sensor 72 is arranged on the structural part 6.

[0046] Specifically, the sensor 72 is a proximity sensor, which is fixedly connected to the structural part 6 by a sensor press-fit part 721 through a screw. The sensor 72 detects the metal part 71 by electromagnetic induction. The sensor 72 has a coil inside, which generates a high-frequency magnetic field after being energized. When the metal part 71 enters the electromagnetic field range, eddy current will be generated inside the metal part 71, causing the coil to oscillate at a variable frequency. The sensor 72 outputs a signal by detecting this change.

[0047] In this embodiment, the metal part 71 is an iron sheet, which is fixedly connected to a fixing part 73. The fixing part 73 is made of plastic material. The number of metal parts 71 is two, which are embedded in the fixing part 73 and fixedly connected thereto. The fixing part 73 is arranged outside the end of the rotating shaft 3, and abuts against the second bearing 42 and the structural part 6, respectively.

[0048] As shown in Figure 1 A wafer cleaning device includes a cleaning box body 11, a driving wheel mechanism 12 arranged in the cleaning box body 11 for driving the wafer 9 to rotate, a brushing mechanism 13 for cleaning the surface of the wafer 9, and the above-mentioned driven mechanism. The number of driving wheel mechanisms 12 is two, which are arranged on both sides of the driven mechanism, respectively.

[0049] The principle of the wafer 9 rotation number detection is as follows: the wafer 9 is clamped in the slot 541 of the clamping groove 54, the clamping groove 54 is fixed on the rotating shaft 3 through the connecting part 52 and the fixing part 53, the rotating shaft 3 passes through the rotary transmission assembly 4, the outer ring of the rotary transmission assembly 4 will not rotate under the abutting action of the structural part 6, and the metal part 71 rotates together with the rotating shaft 3; the wafer 9 rotates under the driving of the driving wheel mechanism 12, drives the rotating shaft 3 to rotate, and the fixing part 73 drives the metal part 71 to rotate together, and the sensor 72 can detect the actual rotation speed of the wafer 9 through electromagnetic induction with the metal part 71.

[0050] Due to the rotation of the rotating shaft 3, the base 2 and the structural part 6 will not rotate, and the moment of inertia of the rotating shaft 3 and the wafer supporting unit 5 is less than 35 kg*mm 2 , preferably, the moment of inertia is less than 30 kg*mm 2 .

[0051] The driven mechanism is also provided with a liquid passage 8, which includes a liquid inlet channel 81 located in the structural part 6, at least two branch channels 82 branched from the liquid inlet channel 81, a liquid storage channel 83 arranged in the mounting cavity 21 corresponding to the rotary transmission assembly 4, and a detour channel 84 arranged between the base 2, the sleeve part 51 and the rotating shaft 3, and the height of the bottom of the liquid storage channel 83 is lower than the height of the inlet of the detour channel 84. Figure 2 The height of the inlet of the detour channel 84 is H1, the height of the bottom of the liquid storage channel 83 is H2, and H1 is above H2. The liquid storage channel 83 refers to the area surrounded by the inner wall of the limiting part 43, the outer wall of the rotating shaft 3, the end face of the first bearing 41 and the end face of the second bearing 42. The detour channel 84 includes the gap between the outer wall of the rotating shaft 3 and the inner wall of the first bearing 41, the gap between the end face of the first bearing 41 and the inner end face of the base 2, the gap between the rotating shaft 3 and the opening of the base 2, the gap between the sleeve part 51 and the base 2, and the internal gap of the first bearing 41.

[0052] In this embodiment, as shown in Figure 5 , Figure 6 , the number of branch channels 82 is four, and the four branch channels 82 are inclined and diverged outward from the liquid inlet channel 81, and the adjacent branch channels 82 have equal spacing. The liquid flow in the liquid inlet channel 81 is 30-70 ml / min, and the liquid flow in each branch channel 82 is 7.5-17.5 ml / min.

[0053] The structural part 6 is connected with the external conduit 61, so that the liquid is transported from the external conduit 61 to the liquid inlet channel 81 in the structural part 6, enters the branch channels 82, enters the liquid storage channel 83 through the gap between the rotating shaft 3 and the second bearing 42, and enters the detour channel 84 through the gap between the rotating shaft 3 and the first bearing 41 once the liquid in the liquid storage channel 83 accumulates more.

[0054] Fluid can be continuously supplied through the inlet channel 81, meaning the liquid in the liquid passage 8 is in a continuous flow state; alternatively, a check valve can be installed at the beginning of the liquid passage 8, and a dynamic sealing ring 85 can be installed at the end of the liquid passage 8. The check valve and the dynamic sealing ring 85 work together to close the liquid passage 8, such as... Figure 13 , Figure 14 As shown, after the liquid inlet channel 81 completes one liquid transfer, the liquid storage channel 83 is filled with liquid. Specifically, the space between the first bearing 41 and the second bearing 42 is filled with liquid.

[0055] In this embodiment, the fluid is water. Water flows into the liquid inlet channel 81 of the structural component 6 through the external conduit 61. The water path is divided into four paths through the branch channel 82 and flows into the liquid storage channel 83, that is, into the mounting cavity 21 containing the first bearing 41 and the second bearing 42. At this time, since the water is divided into four branches, its flow rate is suppressed in the first step, that is, the flow rate is reduced for the first time. When the water level in the mounting cavity 21 is level with the inlet of the detour channel 84, the inlet of the detour channel 84 is the gap between the first bearing 41 and the rotating shaft 3. The liquid is discharged through the detour channel 84, and the flow rate is suppressed in the second step, that is, the flow rate is reduced for the second time. Then, the water will flow into the cleaning tank 11 through the detour channel 84, and the flow rate is suppressed in the third step, that is, the flow rate is reduced for the third time.

[0056] The three-stage liquid flow rate suppression enables water lubrication of the first bearing 41 and the second bearing 42 without significantly affecting the rotation of the rotating shaft 3 due to fluid flow, thus ensuring the accuracy of wafer 9 rotation speed monitoring.

[0057] When the liquid passage 8 is closed by using a check valve and a dynamic sealing ring 85, and the liquid storage passage 83 is filled with liquid, the first bearing 41 and the second bearing 42 are water lubricated. At the same time, the water-filled fluid passage 8 can reduce or avoid the disturbance of the bearing balls inside the mounting cavity 21 caused by fluid disturbance, thus ensuring the stability of the overall mechanism.

[0058] The above specific embodiments are used to explain and illustrate the present invention, but not to limit the present invention. Any modifications and changes made to the present invention within the spirit and scope of the claims shall fall within the protection scope of the present invention.

Claims

1. A driven mechanism for a wafer cleaning apparatus, characterized in that, include: The base (2) is used to fix the wafer cleaning device (1) to the wafer cleaning device (1). The base (2) has a hollow interior forming an installation cavity (21). A rotating shaft (3) is rotatably connected to the mounting cavity (21) via a rotational transmission assembly (4), with its first end (31) extending from the base (2); The wafer support unit (5) is concentrically and coaxially connected to the first end (31) of the rotating shaft (3) for supporting the wafer (9); the wafer support unit (5) includes a sleeve part (51) connected to the rotating shaft (3), a connecting part (52) extending radially outward from the end of the sleeve part (51), a fixing part (53) cooperating with the connecting part (52), and a slot (54) clamped between the connecting part (52) and the fixing part (53), the slot (54) being used to contact the wafer (9), and the sleeve part (51) covering the periphery of the base (2) in both radial and axial directions; The structural component (6) is sealed to the base (2), and at least part of it extends into the mounting cavity (21) and can abut against the rotary transmission assembly (4); The sensor assembly (7), at least partially connected to the rotating shaft (3), is used to monitor the number of rotations of the rotating shaft (3) relative to the base (2); When the wafer (9) rotates and drives the wafer support unit (5) to rotate, the rotating shaft (3) rotates synchronously, driving at least part of the sensor assembly (7) to rotate, so as to monitor the number of revolutions of the wafer (9).

2. The driven mechanism for a wafer cleaning apparatus according to claim 1, characterized in that: The rotary transmission assembly (4) includes a first bearing (41), a second bearing (42), and a limiting member (43) abutting between the first bearing (41) and the second bearing (42).

3. The driven mechanism for a wafer cleaning apparatus according to claim 2, characterized in that: The slot (54) is radially corresponding to the limiting member (43).

4. The driven mechanism for a wafer cleaning apparatus according to claim 1, characterized in that: The sensor assembly (7) includes a metal body (71) and a sensor (72) that cooperates with the metal body (71). The metal body (71) is connected to the second end (32) of the rotating shaft (3), and the sensor (72) is located on the structural member (6).

5. The driven mechanism for a wafer cleaning apparatus according to claim 1, characterized in that: A liquid passage (8) is provided, which includes at least an inlet channel (81) located in the structural member (6), at least two branch channels (82) diverted from the inlet channel (81), a liquid storage channel (83) located in the mounting cavity (21) corresponding to the rotary transmission assembly (4), and a detour channel (84), wherein the bottom of the liquid storage channel (83) is at a height less than the inlet of the detour channel (84).

6. The driven mechanism for a wafer cleaning apparatus according to claim 5, characterized in that: The liquid flow rate in the inlet channel (81) is 30-70 ml / min, and the liquid flow rate in the branch channel (82) is 7.5-17.5 ml / min.

7. The driven mechanism for a wafer cleaning apparatus according to claim 5, characterized in that: The liquid passage (8) is provided with a dynamic sealing ring (85) at its end and a one-way valve at its beginning to close the liquid passage (8) and fill the liquid storage channel (83) with liquid.

8. The driven mechanism for a wafer cleaning apparatus according to claim 1, characterized in that: The moment of inertia of the rotating shaft (3) and the wafer support unit (5) is less than 35 kg*mm. 2 .

9. A wafer cleaning apparatus, characterized in that, It includes a cleaning chamber (11), a drive wheel mechanism (12) disposed inside the cleaning chamber (11) for driving the wafer (9) to rotate, a brushing mechanism (13) for cleaning the surface of the wafer (9), and a driven mechanism as described in any one of claims 1-8.

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